Boardtrack/bobber vintage motorcycle thing

I hate the **** Chinese kits with a passion. So I found an tiny little engine and I'm gonna see if it works. I took a piece of scrap pipe and bent a new downtube for a Schwinn I had laying around. After hacking out a section of the down tube I welded it in. I cut out a plate to mount the Briggs and Stratton and have started collecting parts for the rest of the build.

This evening I installed a different, rigid fork for tire clearance on the bike. I laced up a MTB disk brake front hub on to a Surly Large Marge rim. It's wider than any other MTB rim and with 2.4" tires they should be short and fat. I'm hoping the 24" wheels will give the bike a longer look without having to stretch the frame.

I took an old set of cruiser bars that had the right bend and chopped them off so I had a nice, narrow set of boardtrack looking bars and installed inverted levers.

Yeah it is a bit of extra weight. Not much more than an standard set of heavy duty cruiser wheels though. I'm going to run a 203mm disk rotor on the front. I use them on my downhill bike and they provide a lot of power. I'm not sure the little briggs will power it though.

One awesome build you got going there. I have the plans that were in on of the early mags. like popular machanics back in the 40's or 50's they can also be found on gasbike web site. If you post or PM me your email I can send them.
I love these home builds I am working on a Shaw clone will be close to what you are doing but taller frame......Curt

I just realized that that thing you cut off. Was that a breather? If did you open one up somewere else like the valve tapet cover?

I had some plate left over from another project and cut out a mount for the two pillow bearings. The pillow bearings hold a 3/4" shaft I cut down to 10". I got the bearing mount welded to the seat tube, so the jackshaft is now in. I need to buy one more pillow bearings tomorrow.

Since I hacked away my oil filler/check on the front of the motor, I needed to make a new one. I bought some brass pipe threaded on two ends, a 90* elbow and a brass cap. I also purchased a pipe thread tap so I can tap the block and put in a new filler/checker. I'm going to solder in a piece of bicycle spoke into the cap so I have an oil checker.

I also got my throttle lever welded on to the handlebar. I'm using an old Shimano 3-speed shifter flipped upside down and welded to the bar. It took some modifications to make it work. .

I had some plate left over from another project and cut out a mount for the two pillow bearings. The pillow bearings hold a 3/4" shaft I cut down to 10". I got the bearing mount welded to the seat tube, so the jackshaft is now in. I need to buy one more pillow bearings tomorrow.

Since I hacked away my oil filler/check on the front of the motor, I needed to make a new one. I bought some brass pipe threaded on two ends, a 90* elbow and a brass cap. I also purchased a pipe thread tap so I can tap the block and put in a new filler/checker. I'm going to solder in a piece of bicycle spoke into the cap so I have an oil checker.

I also got my throttle lever welded on to the handlebar. I'm using an old Shimano 3-speed shifter flipped upside down and welded to the bar. It took some modifications to make it work. .

The shifter looked like this-

I have a lot of pictures. I will have to post them tomorrow.

Click to expand...

Keep in mind weedeaters have some little triger throttles that clamp to the shafts.

Here's one of those "Hey Beau can you use this metal" moments. A piece of a store fixture happen to fit a euro BB quite well.

A trip to Fleet Farm (a.k.a. The Man's Mall) turned out to be really helpful.

I found collars that fit different size sheaves (pulley's) that had a 3/4" bore. I had to buy the collars and sheaves separate and will have to weld them together. The sheave slides on tightly to the collar too.

I stumbled upon 1/4" copper tubing in a 10' roll for a little over $5. It will fit 4mm or 5mm cable housing and I'm gonna use it to hide the throttle cable and brake cables.

Post some pictures of the pullys. Pean the end of the spoke flat and file a full mark on it? I like your rear pully I will be doing the same except I will be useing a 24" on a 26" wheel. I am building a turn table to clamp the rim on so I can cut and weld it. I want to cut the center out and weld it back together, no spoke holes.Then I will cut the outer round lip off ( its a deep V type rim with the narrow center ) Then will put both rims on table and bend up some Z shape brackets and rivit them together.......Curt

I have the jack shaft mocked up now. I'm gonna need to gusset the mount a bit, but it should work good. I also need to shorten the jack shaft. Final word...It's not gonna pedal. I'm probably gonna have a tensioner pulley mounted on the chainstay too.